The long-listing of William Trevor and JM Coetzee for the Booker Prize last month could hardly have come as a surprise to literary fiction fans. Though their novels hadn’t yet been published when the announcement was made, the authors’ pedigree is world-class – Cork-born Trevor has won the Whitbread Award three times; and in 2003, South African-born Coetzee took home the Nobel Prize for Literature.

Like their American rival Philip Roth, Trevor and Coetzee have moved into the late phase of their careers – Coetzee is 69,Trevor is 81 – with striking ease, continuing to write with uncommon insight, vitality and passion. There is great truth in their visions, and none can hide before the steady, piercing quality of their gaze. The darkness and thrum of menace in both men’s work is often striking – though Coetzee is the far more political of the two; the more troubled, rootless, questioning author.

In Summertime, Coetzee has produced a fictionalised memoir – the completion of a trilogy that began with Boyhood – that is intellectually rigorous and challenging – and extremely rewarding to read, particularly if you’re already a Coetzee fan.

The structure of the book is simple, but subversively original. A young English biographer is gathering together material for a book about the deceased writer John Coetzee. Focusing on the years 1972-1977, when Coetzee was in his 30s, the biographer interviews a number of people who knew Coetzee: his favourite cousin Margot; a Brazilian dancer; a married woman with whom he had an affair; and some of his friends and colleagues.

They describe him variously as cold, awkward, occasionally funny, heartless, flat-footed, sexless, a man who ‘‘looked out of place, like one of those flightless birds’’. To a striking extent, Coetzee uses the voices of other characters in this book as a stick to beat himself with, and also as an opportunity to present himself – perhaps – as he really is: a diffident, awkward individual, a man who longs to be a romantic or an existentialist, but lacks the natural capacity to be either: ‘‘It was all just an idea in his head, not an urge rooted in his body.”

Towards the end of the book, the Brazilian dancer Adriana speaks frankly of her feelings about Coetzee. ‘‘Tell me, am I wrong about John Coetzee? Was he really a great writer? Because to my mind, a talent for words is not enough if you want to be a great writer. You have also to be a great man. And he was not a great man. He was a little man, an unimportant man.”

Her comments cut to the core of this book. Coetzee seems to question the validity of the towering reputation he has amassed, and the writing enterprise itself. Or could he be undermining himself to counteract the natural conceit involved in producing a memoir? Reclusive by nature and media-shy as Coetzee is, it’s impossible to know – and an internet search to acquire further detail turns up more questions than answers.

The degree of truth contained in this fictionalised memoir is also impossible to judge. Are any or all of these characters real?

Very possibly. Either way, the effects of the narrative decisions he has made are fascinating and haunting. In Coetzee’s fiction – I’d recommend in particular Life & Times of Michael K( 1983),Age of Iron (1990) and Disgrace (1999) – what comes through most strongly is his characters’ sense of anguish: they long to feel, to love, to be natural – but these ambitions are beyond them, flitting out of their grasp.

Via this memoir, you gather that Coetzee shares their feelings. Like his character Lucy in Disgrace, Coetzee – clearly depicted throughout as highly altruistic – also feels deep shame about South Africa’s past. Of his move to Australia, his former colleague Martin explains that he could not have continued to live in South Africa.

‘‘Our attitude was that our presence there was legal, but illegitimate. We had an abstract right to be there, a birthright, but the basis of that right was fraudulent.”

Coetzee’s cousin Margot recalls the day Coetzee’s truck broke down again in the middle of the semi-desert region of the Karoo, leaving them stranded for the night with no food or blankets. Asked why he didn’t get his truck fixed properly by a competent person, he said he fixed it himself because ‘‘of our long history of making other people do our work for us while we sit in the shade and wait’’.

In common with most of Coetzee’s other work, Summertime is beautifully structured, fluid and perfectly paced. While of far more interest to Coetzee fans than the casual reader, it easily deserves a place on the Booker Prize shortlist, when it is announced on September 8.

Will William Trevor have an equal or better chance? Certainly, Love and Summer is a far more traditional, easy-to access affair. Unlike Coetzee, Trevor is not seeking to remake the form of the novel. Instead, he seems to be plunging deeper into himself, drawing upon his every skill to pen a novel in which the actual story threads are so subtle, that it’s difficult to see how Trevor has woven it together. Yet he writes with such confidence, detail and verve that his slight story is injected with a huge boost of power.

Set around the 1950s, it seems (there is no precise date given), the novel begins with an ending -Mrs Eileen Connulty has died, and her body is passing through the Irish town of Rathmoye, where nothing ever happens, to the Church of the Most Holy Redeemer. ‘‘Her daughter she was glad to part from; her son – now in his fiftieth year, her pet since first he lay in her arms as an infant -Mrs Connulty had wept to leave behind.”

The daughter of the wealthy Mrs Connulty is a ferocious, menacing, suspenseful presence in the novel. A tragedy she experienced at an early age has ruined her, made her bitter and suspicious. Now she watches everyone from the windows of the lodging house the Connulty family established in 1903, and she gathers information like a rabid detective.

She is the first to witness the friendship spring up between outsider Florian Kilderry and Ellie, a young convent girl who has married the farmer Dillahan. She sees immediately that more is going on than meets the eye: ‘‘Ellie Dillahan was victim enough without the attentions of a suave photographer. In Miss Connulty’s bristling imagination he was already a plunderer.”

Trevor vividly shows the emptiness of Miss Connulty’s life – having long ago lost her capacity to be the prime agent in her own life, she now acts like a malicious ghost in the lives of others. A sad highlight of her day is to spend time trying on her mother’s jewellery that now is hers: ‘‘strings of lapis and jade, garnet and amber, the sapphire earrings’’. There seems to be nothing more substantial to do.

As for Ellie, one of the most heartbreaking moments in this book is the depiction of how much a relationship can mean to one person – and how fleeting and insubstantial it can seem to another, namely Florian.

You come away from this book feeling an indefinable sense of loss: so many of Trevor’s characters are struggling to come to terms with their own lives – and their lives are often so hauntingly sad.

Unlike his excellent, zippily plot-driven Booker-nominated 2002 novel, The Story of Lucy Gault, Love and Summer is an extremely elegant, but subtle, novel – perhaps too subtle. Although Trevor hides it well, the novel is somewhat lacking in story – the characterisation is brilliant, but the tale itself doesn’t last as long as it should in the mind. With fellow long-listed nominees Colm Tóibín and Sarah Waters both having produced strong, more modern takes on the historical novel, Trevor may find himself condemned once again to being a Booker bridesmaid.

Ultimately, if only one of these two authors goes forward to the shortlist on September 8, it should be Coetzee.